The purpose is to elicit molecular details of conformational kinetics in polypeptides and DNA. An eventual aim is to understand the mechanisms and pathways of DNA double helix formation, of protein folding, and of denaturation and renaturation. A mathematical model of the rates for passing between the various configurational states was previously formulated. Molecular states are determined by specification for each residue of a helical or random coil conformation. Averages are performed over all possible conformations. Calculated results have been compared with experiments on DNA. Effects of perturbation direction and size were calculated; strong dependences were observed, mostly in agreement with corresponding experiments. The effects of including a bimolecular reaction for the formation of the first DNA helix unit were investigated; for usual conditions this effect is small. BIBLIOGRAPHIC REFERENCE: Jernigan, R.L. and Szu, S.C.: Polypeptide Relaxation with Configurationally Dependent Internal Friction. J. Poly. Sci. Symp. 54: 271-281, 1976.